{"openapi":"3.1.0","info":{"title":"Institutional Stock Ownership API","version":"1.0.0","description":"Institutional (13F) ownership of US stocks, live and keyless, from Nasdaq's public company data. Every quarter the big money — Vanguard, BlackRock, State Street, hedge funds and pensions — must disclose its US equity holdings in 13F filings, and that ownership is one of the most-watched fundamentals: how much of a stock is held by institutions, which funds hold it, and whether smart money is accumulating or distributing it. The ownership endpoint gives a stock's institutional-ownership summary: the percentage of the company held by institutions, the total shares outstanding, the total dollar value of institutional holdings and the count of holders. The holders endpoint is the league table of the largest institutional holders — each fund with the shares it holds, how that changed last quarter (shares and percent), the dollar value and the filing date. The activity endpoint is the accumulation/distribution view: how many institutions increased, decreased, opened (new) or closed (sold-out) their positions and the shares involved, plus a net read on whether institutions were net buyers or sellers. This is the 13F institutional-ownership cut — distinct from the insider feed (company officers' and directors' own Form 4 trades), the short-interest feed (shares sold short and days-to-cover) and the analyst, quote and movers feeds. 13F holdings are disclosed quarterly, so the data updates each filing season, not intraday. Shares are counts, values in US dollars, percentages as reported. No key, nothing stored.","contact":{"name":"PremiumApi","url":"https://www.oanor.com/by/premiumapi"}},"servers":[{"url":"https://api.oanor.com/institutions-api","description":"oanor gateway"}],"tags":[{"name":"Ownership"},{"name":"Holders"},{"name":"Activity"},{"name":"Meta"}],"components":{"securitySchemes":{"oanorKey":{"type":"apiKey","in":"header","name":"x-oanor-key","description":"Get your key at https://www.oanor.com/developer/keys"}}},"security":[{"oanorKey":[]}],"paths":{"/v1/ownership":{"get":{"operationId":"get_v1_ownership","tags":["Ownership"],"summary":"Institutional ownership summary for a stock","description":"","parameters":[{"name":"symbol","in":"query","required":true,"description":"US stock ticker","schema":{"type":"string"},"example":"AAPL"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"One US stock's institutional (13F) ownership summary: institutional_ownership_pct is the share of the company held by institutions, with the total shares outstanding, the total dollar value of institutional holdings and the number of institutional holders. A high and rising institutional ownership signals strong professional conviction. 13F data is disclosed quarterly. Source data is live from Nasdaq.","source":"Nasdaq public institutional-holdings feed (api.nasdaq.com), keyless","symbol":"AAPL","total_shares_outstanding":14687000000,"total_institutional_shares":11014219744,"institutional_ownership_pct":74.99,"total_institutional_holders":6438,"total_institutional_value_usd":3256134000000},"meta":{"timestamp":"2026-06-12T19:35:53.837Z","request_id":"50efff3b-8677-49ce-b5e8-b290d12a9e5a"},"status":"ok","message":"Ownership retrieved successfully","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/holders":{"get":{"operationId":"get_v1_holders","tags":["Holders"],"summary":"Largest institutional holders with quarterly changes","description":"","parameters":[{"name":"symbol","in":"query","required":true,"description":"US stock ticker","schema":{"type":"string"},"example":"NVDA"},{"name":"limit","in":"query","required":false,"description":"Number of holders (1-25)","schema":{"type":"string"},"example":"15"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"The largest institutional holders of a US stock, ranked by position value — each fund with the shares it holds, how that changed in the latest quarter (shares and percent; positive = it added, negative = it trimmed), the dollar value of the stake and the filing date. Vanguard, BlackRock and State Street top most large-cap lists. market_value_usd is the position value (Nasdaq reports it in thousands; converted here to dollars). Pass limit (1-25, default 15). 13F data is quarterly.","count":15,"source":"Nasdaq public institutional-holdings feed (api.nasdaq.com), keyless","symbol":"NVDA","holders":[{"date":"12/31/2025","name":"Vanguard Group Inc","shares_held":2266683275,"shares_change":43149475,"market_value_usd":464375403000,"shares_change_pct":1.941},{"date":"3/31/2026","name":"Blackrock, Inc.","shares_held":1925533174,"shares_change":-18279710,"market_value_usd":394483981000,"shares_change_pct":-0.94},{"date":"3/31/2026","name":"Vanguard Capital Management Llc","shares_held":1538550382,"shares_change":1538550382,"market_value_usd":315202817000},{"date":"3/31/2026","name":"State Street Corp","shares_held":993885601,"shares_change":2405112,"market_value_usd":203617343000,"shares_change_pct":0.243},{"date":"3/31/2026","name":"Fmr Llc","shares_held":993852968,"shares_change":22789685,"market_value_usd":203610658000,"shares_change_pct":2.347},{"date":"3/31/2026","name":"Geode Capital Management, Llc","shares_held":601327167,"shares_change":12524074,"market_value_usd":123193897000,"shares_change_pct":2.127},{"date":"3/31/2026","name":"Vanguard Portfolio Management Llc","shares_held":510126721,"shares_change":510126721,"market_value_usd":104509661000},{"date":"3/31/2026","name":"Jpmorgan Chase & Co","shares_held":447798884,"shares_change":-8342254,"market_value_usd":91740557000,"shares_change_pct":-1.829},{"date":"3/31/2026","name":"Price T Rowe Associates Inc /Md/","shares_held":370102688,"shares_change":-3085238,"market_value_usd":75822938000,"shares_change_pct":-0.827},{"date":"3/31/2026","name":"Morgan Stanley","shares_held":342954346,"shares_change":19220362,"market_value_usd":70261057000,"shares_change_pct":5.937},{"date":"12/31/2025","name":"Norges Bank","shares_held":333748700,"shares_change":8494803,"market_value_usd":68375096000,"shares_change_pct":2.612},{"date":"3/31/2026","name":"Northern Trust Corp","shares_held":252741836,"shares_change":-1047967,"market_value_usd":51779220000,"shares_change_pct":-0.413},{"date":"3/31/2026","name":"Ubs Am, A Distinct Business Unit Of Ubs Asset Management Ame","shares_held":198975239,"shares_change":3095238,"market_value_usd":40764057000,"shares_change_pct":1.58},{"date":"3/31/2026","name":"Capital Research Global Investors","shares_held":193037700,"shares_change":21474958,"market_value_usd":39547634000,"shares_change_pct":12.517},{"date":"3/31/2026","name":"Bank Of America Corp /De/","shares_held":191200989,"shares_change":4019505,"market_value_usd":39171347000,"shares_change_pct":2.147}]},"meta":{"timestamp":"2026-06-12T19:35:53.971Z","request_id":"6c12c048-384a-4f76-b8af-b1d588f4f7bf"},"status":"ok","message":"Holders retrieved successfully","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/activity":{"get":{"operationId":"get_v1_activity","tags":["Activity"],"summary":"Accumulation/distribution — increased/decreased/new/sold-out","description":"","parameters":[{"name":"symbol","in":"query","required":true,"description":"US stock ticker","schema":{"type":"string"},"example":"MSFT"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"The institutional accumulation/distribution view for a US stock last quarter: how many institutions increased, decreased, held, opened (new) or closed (sold-out) their positions and the shares involved. net_share_flow is increased minus decreased shares (positive = institutions added net shares); net_new_positions is new minus sold-out holders; institution_sentiment reads buyers (increased + new) against sellers (decreased + sold-out). The smart-money flow signal. 13F data is quarterly.","source":"Nasdaq public institutional-holdings feed (api.nasdaq.com), keyless","symbol":"MSFT","new_positions":{"shares":748891376,"holders":225},"held_positions":{"shares":4965234736,"holders":341},"net_share_flow":727582313,"net_new_positions":8,"sold_out_positions":{"shares":22115490,"holders":217},"decreased_positions":{"shares":239633901,"holders":2777},"increased_positions":{"shares":967216214,"holders":3565},"institution_sentiment":"accumulating","total_institutional_shares":6172084851},"meta":{"timestamp":"2026-06-12T19:35:54.096Z","request_id":"0931b062-8520-41db-9873-43271606b9e7"},"status":"ok","message":"Activity retrieved successfully","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/meta":{"get":{"operationId":"get_v1_meta","tags":["Meta"],"summary":"Service metadata","description":"","parameters":[],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"ownership and activity take symbol (a US ticker, required). holders takes symbol (required) and limit (1-25, default 15). meta takes no parameters. 13F holdings are disclosed quarterly, so values update each filing season, not intraday. Shares are counts, values in US dollars, percentages as reported. A short ~5-minute protective cache fronts the upstream.","source":"Nasdaq public institutional-holdings feed (api.nasdaq.com), keyless, live","service":"institutions-api","endpoints":{"GET /v1/meta":"This document.","GET /v1/holders":"Largest institutional holders with quarterly changes (symbol=AAPL, limit).","GET /v1/activity":"Accumulation/distribution — increased/decreased/new/sold-out positions (symbol=AAPL).","GET /v1/ownership":"Institutional ownership summary for a stock (symbol=AAPL)."},"description":"Institutional (13F) ownership of US stocks, live and keyless, from Nasdaq's public company data. Each quarter institutions disclose their US equity holdings; this exposes how much of a stock they own, which funds hold it and whether they are accumulating or distributing. The ownership endpoint gives the institutional-ownership summary (percent owned, shares outstanding, total value, holder count); holders is the league table of the largest institutional holders with their quarterly position changes; activity is the accumulation/distribution breakdown (increased/decreased/new/sold-out positions) with a net smart-money read. The 13F institutional-ownership cut — distinct from the insider feed (officers' Form 4 trades), the short-interest feed (shares shorted, days-to-cover) and the analyst, quote and movers feeds.","upstream_status":"ok","sample_ownership":{"symbol":"AAPL","institutional_ownership_pct":74.99}},"meta":{"timestamp":"2026-06-12T19:35:54.217Z","request_id":"4462e943-5234-4974-9177-04b14a0ab731"},"status":"ok","message":"Meta","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}}},"x-oanor-pricing":[{"slug":"free","name":"Free","price_cents_month":0,"monthly_call_quota":700,"rps_limit":2,"hard_limit":true},{"slug":"starter","name":"Starter","price_cents_month":2400,"monthly_call_quota":26000,"rps_limit":6,"hard_limit":true},{"slug":"pro","name":"Pro","price_cents_month":8300,"monthly_call_quota":130000,"rps_limit":16,"hard_limit":true},{"slug":"scale","name":"Scale","price_cents_month":23700,"monthly_call_quota":660000,"rps_limit":40,"hard_limit":true}],"x-oanor-marketplace-url":"https://www.oanor.com/api/institutions-api"}